mcarufe Posted July 3, 2007 Report Share Posted July 3, 2007 Peter, Is the species of the sample a controled variable? Mike Quote Link to comment Share on other sites More sharing options...
Ratcliffiddles Posted July 3, 2007 Report Share Posted July 3, 2007 quote: Originally posted by: mcarufe Peter, Is the species of the sample a controled variable? Mike Hi Mike, Dendro analysis is done within one species, and that is how the reference data is organised, but some related tree species have some correlation between each other as to their growth. As for instruments, we are mostly dealing with spruce, so that is the reference we mainly look at. However, some other references from, f.e Douglas Fir also match some instruments, (at the same date than spruce) sometime better than the spruce data, but it is known that other conifers than spruce were used on fronts of instruments. The vast majority is spruce, though there are pockets in history were it wasn't necessarily so. Peter Quote Link to comment Share on other sites More sharing options...
Wolfjk Posted July 3, 2007 Report Share Posted July 3, 2007 Hi Peter, Thanks for your post. quote: What people seem to forget, is that the wood mostly used for violins is highly selected, it is not generally compression wood, it is normally straight grained, quarter sawn, no knots, no resin pockets. It is therefore ideal material because it is as far as nature allowed, free from defects. You may think it strange, but the tight even(apparently) growth often yealds the best dendrochronology results. Peter Would not this add to the uncertainity of viewing tree rings from different periods of time? My perception is that one needs known unusual historical events that leave a traces in the tree rings: volcanic erruptions, floods, heave snowfall, cold snaps, wet/ dry summers, late springs and e.t.c. Here is another photo of John Tophams article of five violins that came from the same tree. Here you can tell by just looking at graph that there are many common features: Yet there are differences when growing, or wheather conditions effected some part of the tree! It seems, the tree knows when a butterfly lands on its leaf!. Another problem is the exact locations of the reference material. If you look at a house in York that was built in the 17th century, it might have timbers from roman times! Cheers Wolfjk Quote Link to comment Share on other sites More sharing options...
Ratcliffiddles Posted July 3, 2007 Report Share Posted July 3, 2007 quote: Hi Wolfjk, . You may think it strange, but the tight even(apparently) growth often yealds the best dendrochronology results. Peter Hi peter Would not this add to the uncertainity of viewing tree rings from different periods of time? My perception is that one needs known unusual historical events that leave a traces in the tree rings: volcanic erruptions, floods, heave snowfall, cold snaps, wet/ dry summers, late springs and e.t.c. Another problem is the exact locations of the reference material. If you look at a house in York that was built in the 17th century, it might have timbers from roman times! Cheers Wolfjk That is why I said, you may think it strange. but the overwhelming dendro evidence points towards the opposite of your perception, (not just your perception, as this way of thinking seems to be "logical"). As an example, out of the 104 instruments measured, described as either Kloz /Kloz school, or 18th Century Mittenwald, mostly showing very tight and even growth, only 5 haven't dated. The rest normally comes up with very high and unmistakable results. The exact locations of reference chronologies are known for spruce, but, as previously mentioned, because some of those chronologies often correlate well, even if far apart, the exact location of a sample(violin wood) is rarely very precise. Though when the wood only matches chronologies from a particular area, there obviously is a relationship, especially if that area was subject to condition particular to it, microclimates, exposure, soil composition and all the other factors contributing to growth. Peter Quote Link to comment Share on other sites More sharing options...
mcarufe Posted July 3, 2007 Report Share Posted July 3, 2007 Peter, No doubt that the science you are using is very useful, but let me be up front and state my concerns. In light of dendro testing casting a doubt to authenticity of historical instruments, what if makers used spruce from more exotic locations that had highly statistical similarities to instruments to other spruce in other locations from different time periods. Would not the test the require the location variable also be understood to eliminate this error? On another thread, I pointed out a possibly silly idea that some of the masters experimented with exotic tonewood if they had the oppurtunity. This could at least account for variations and some mysteries. Also and maybe more disturbing would be deliberate presentation of a dendro identified samples to fake on a higher level. Mike Carufe Quote Link to comment Share on other sites More sharing options...
Ratcliffiddles Posted July 3, 2007 Report Share Posted July 3, 2007 quote: Originally posted by: mcarufe Peter, No doubt that the science you are using is very useful, but let me be up front and state my concerns. In light of dendro testing casting a doubt to authenticity of historical instruments, what if makers used spruce from more exotic locations that had highly statistical similarities to instruments to other spruce in other locations from different time periods. Would not the test the require the location variable also be understood to eliminate this error? On another thread, I pointed out a possibly silly idea that some of the masters experimented with exotic tonewood if they had the oppurtunity. This could at least account for variations and some mysteries. Also and maybe more disturbing would be deliberate presentation of a dendro identified samples to fake on a higher level. Mike Carufe Hello Mike, I think your concerns are very pertinent, but regarding spruce from different locations and time period having similar statistical results for an overlapping spurious timespan, I just don't think that situation exists, at least not for a long enough period, that is why a minimum of fifty years growth is required to make an assessment. Furthermore one of the principles of applied dendrochronology is the repeatability of results against several chronologies, so one good result is never enough to come to a conclusive date. As I mentioned in a previous post, if such a period of time with statistically similar attributes existed, it would show up in an analysis repeatedly, alongside the "correct" period. And I have not come across this situation (as yet). On your second point about possible fakes to a higher level, there may well be people out there, trying to find an old piece of spruce, matching the characteristic of wood used by the Cremonese, but those people have a big task in front of them, as the precise growing location of this timber remains unknown to this day. But you are right, as here we are not just talking about 17 & 18th century instruments. Modern fakes of 19th and 20th century makers are commonly seen, and the growing awareness of dendrochronology will no doubt, lead the devious maker to acquire 100year old wood from a given location, which is far more possible than to find usable 300 year old pruce, but there again, when it works, dendro will only positively identify the date of the wood and possibly a growing location, but NOT the maker. Peter Quote Link to comment Share on other sites More sharing options...
mcarufe Posted July 3, 2007 Report Share Posted July 3, 2007 Quote Peter: ________________________________________________________________________________ ____ regarding spruce from different locations and time period having similar statistical results for an overlapping spurious timespan, I just don't think that situation exists, at least not for a long enough period, that is why a minimum of fifty years growth is required to make an assessment. ________________________________________________________________________________ ____ If it ever does come up, you owe me a beer. Mike Carufe Quote Link to comment Share on other sites More sharing options...
Ratcliffiddles Posted July 3, 2007 Report Share Posted July 3, 2007 quote: Originally posted by: mcarufe Quote Peter: ________________________________________________________________________________ ____ regarding spruce from different locations and time period having similar statistical results for an overlapping spurious timespan, I just don't think that situation exists, at least not for a long enough period, that is why a minimum of fifty years growth is required to make an assessment. ________________________________________________________________________________ ____ If it ever does come up, you owe me a beer. Mike Carufe A barrel! Peter Quote Link to comment Share on other sites More sharing options...
Wolfjk Posted July 4, 2007 Report Share Posted July 4, 2007 Hi Peter, In the above photo from the July Strad, the year 1639 represents some unusual historical, geological or astronomical event. When you see exceptional years like that in your reference material, do you search for a connection to any unusual happening that cuold have caused it? I believe there are some similar years in early English instruments (where ever the wood came from) 1588, 1608 and 1632 are very erratic years. In one of my earlier posts I made a mistake by overloking the similarities of No1 violin with the reference curve. There are some striking matches! Cheers Wolfjk Quote Link to comment Share on other sites More sharing options...
Ratcliffiddles Posted July 4, 2007 Report Share Posted July 4, 2007 quote: Originally posted by: Wolfjk Hi Peter, In the above photo from the July Strad, the year 1639 represents some unusual historical, geological or astronomical event. When you see exceptional years like that in your reference material, do you search for a connection to any unusual happening that cuold have caused it? I believe there are some similar years in early English instruments (where ever the wood came from) 1588, 1608 and 1632 are very erratic years. In one of my earlier posts I made a mistake by overloking the similarities of No1 violin with the reference curve. There are some striking matches! Cheers Wolfjk Hi Wolfjk, It does seem that the conditions in 1639, in those examples led to a substantially narrower ring growth compared with the previous year. In several of the reference I use, this is the case for 1639, and it is so also for other years, 1663 to name another one with similarly narrow ring compared to previous one. Unfortunately, I haven't got the time to research the exact historical events that led to these more unusually narrow or large rings. It is likely to be weather related, and research suggests that different factors have a different effect at different temperatures( and altitude) I am sure it is a fascinating subject but I will happily leave this one for somebody else! Regarding wood from early English instrumens, I have had a quick look at my early English data. And don't really find those years above mentioned to be particularly odd in growth, according to my data. Are you talking about early ealry, or just early? (17th century or 18th) as there seems to be a definite difference between the wood used earlier, and the later 18th century wood. I have a very good idea of the origins of this 18th century wood, but the origins of the earlier one is still very vague. Cheers Peter Quote Link to comment Share on other sites More sharing options...
Wolfjk Posted July 5, 2007 Report Share Posted July 5, 2007 Sorry, double posting Quote Link to comment Share on other sites More sharing options...
Wolfjk Posted July 5, 2007 Report Share Posted July 5, 2007 Hi Peter quote: Regarding wood from early English instrumens, I have had a quick look at my early English data. And don't really find those years above mentioned to be particularly odd in growth, according to my data. Are you talking about early ealry, or just early? (17th century or 18th) as there seems to be a definite difference between the wood used earlier, and the later 18th century wood. I have a very good idea of the origins of this 18th century wood, but the origins of the earlier one is still very vague. I took a fhoto of the sequeces from a BVMA newsletter. The article was written by JT: Here the year 1639 has no significance. The years 1588, 1608 and 1632 seem to signify some event. Cheers Wolfjk Quote Link to comment Share on other sites More sharing options...
Ratcliffiddles Posted July 5, 2007 Report Share Posted July 5, 2007 Hi Wolfk, Yes that's the "very early" data, mostly 17th c. As you say, the years you mentioned generally produced substantially narrower growth in those examples compared to the previous year. 1639 also produced a narrower ring on all those graphs. I don't necesseraly think that those attributes are too significant(ei I don't think the events leading to such rings were cataclismic, but merely weather/ temperature related: combination of lack of rain falls, and slightly lower average temperature and little sun. Some species also react to these events, not only in the year of the event, but also later, affecting the growth of the subsequent year. The graphs seem to indicate a very close relationship between the last six curves, suggesting very close proximity of trees if not same log. So these curves are not necesseraly representative in all aspect of narrow rings, of the general weather pattern over a large area. Peter Quote Link to comment Share on other sites More sharing options...
KB_Smith Posted December 3, 2019 Report Share Posted December 3, 2019 (edited) Hello, I'm new to this forum. I'm trying to contact Peter Ratcliff, hoping you still monitor this forum and topic. I came into possession of an old French violin labeled Alexandre Delanoy, Bordeaux, 1914. I saw earlier in this thread you offered to run dendrochronology on another member's violin if he would send you jpegs. I'm wondering if you are still willing to do that for me if I send you a few full size jpeg images of my violin. I don't know how much of the violin you need to see to do your magic, but I've uploaded some images below for you to look at and let me know if these would work. Each of the original image files below are about 2.5MB high resolution jpegs. Thank you, KB Smith Edited December 4, 2019 by KB_Smith Inserted new photo Quote Link to comment Share on other sites More sharing options...
GeorgeH Posted December 4, 2019 Report Share Posted December 4, 2019 Go here: http://violin-dendrochronology.com Quote Link to comment Share on other sites More sharing options...
Craig Cowing Posted December 10, 2019 Report Share Posted December 10, 2019 Keep in mind that dendrochronology involves drilling a deep hole into the wood. It's ok if you are trying to date the beams in a very old house but in a violin I would caution against it because of the instability it would cause. As some have noted above, take it to an expert and have it examined and appraised. Quote Link to comment Share on other sites More sharing options...
Three13 Posted December 10, 2019 Report Share Posted December 10, 2019 3 minutes ago, Craig Cowing said: Keep in mind that dendrochronology involves drilling a deep hole into the wood. It's ok if you are trying to date the beams in a very old house but in a violin I would caution against it because of the instability it would cause. As some have noted above, take it to an expert and have it examined and appraised. Dendrochronology of violin family instruments doesn’t require any invasive procedures, as the annular rings in the wood are exposed. Quote Link to comment Share on other sites More sharing options...
Dave Slight Posted December 10, 2019 Report Share Posted December 10, 2019 3 hours ago, Craig Cowing said: Keep in mind that dendrochronology involves drilling a deep hole into the wood. It's ok if you are trying to date the beams in a very old house but in a violin I would caution against it because of the instability it would cause. As some have noted above, take it to an expert and have it examined and appraised. For instruments, dendochronological testing is done optically, requiring nothing more than high resolution photos. If you don’t understand the procedures involved, it would be better to post nothing, rather than spread bad information and scaremongering. Quote Link to comment Share on other sites More sharing options...
KB_Smith Posted December 10, 2019 Report Share Posted December 10, 2019 Thanks to all for the input. I'll reach out to Peter again via , per GeorgeH's recommendation. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.